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Date:   Thu, 17 Sep 2020 12:48:24 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Miaohe Lin <linmiaohe@huawei.com>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: avoid possible multiple call to swap_node()
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On Thu, Sep 17, 2020 at 07:44:49AM -0400, Miaohe Lin wrote:
> Cache the swap_node() in a local variable to avoid possible multiple call
> to swap_node(), though compiler may do this for us.

Why don't you find out?  Compare the assembly before and after, see what
the compiler did.